A. Technical Field
The disclosure generally relates to employing a secondary or auxiliary display unit in addition to a main or primary display unit in a computer system. More particularly, the disclosure relates to the use of an auxiliary display unit that can share display responsibility of a host computer with a main display.
B. Related Art
In computer systems today, a single monitor or other type of display unit is connected to a system bus via an interface, such as a video adapter. The system bus couples the monitor to the central processing unit (CPU) of the host computer. The host computer executes instructions requesting that information be retrieved from system memory and sent over the system bus to the display monitor for display.
One known system provides a computer network having a common CPU that can be shared among multiple display terminals and keyboards. In this system, the display terminals are dumb terminals under the control of the CPU. Such a system is typically set up for use by multiple independent users. The advantage of such a system is that the CPU can be centrally located out of sight and away from each of the user's terminals. Thus, space can be freed up at a user's workstation. Another advantage is that all the applications can be stored in a single location rather than having to be installed separately for each user. User display terminals in this type of system suffer the shortcomings discussed below.
Computer operating systems typically run multiple applications concurrently and also maintain multiple applications open. When multiple applications are active or open, various regions of the monitor's display screen provide information regarding or space dedicated to the active applications. For example, a task bar and status notification area typically occupy reserved sections of the display screen. Email and printer status/notification usually is represented as a small icon on the task bar. Also, multiple active applications, for example a spreadsheet application and a word processing application, may occupy different sections of the screen. A transient system message may pop up in a dialog box overlaying an active application. Additionally, if a user inserts a compact disc (CD) into a CD player coupled to the computer system, a separate soft user interface (UI) applet is launched on top of the active application(s) taking up more display space on the display screen. Typically, to recover the primary display screen real estate, the user immediately minimizes the applet window in order to continue working on an underlying active application such as a word processing application.
As is readily apparent from the above description of a typical computer system, substantial portions of the display screen may be occupied by other active applications, dialog boxes, task bars and the like cluttering the display screen and preventing the user from making the most of the display screen for an active application. For example, the user may not want the display screen to show status or notification information or share the display screen area with certain applications. For instance, the user may want to leave substantially all the display screen area for a particular application(s) with which he is working. Further, notifications and dialog boxes often can disrupt or distract a user attempting to focus on a specific application. Thus, there is a need to provide users with the ability to efficiently use and/or manage the display screen of the monitor while still being able to view the status of other applications and receive messages about other applications, without encroaching on the display screen area. The display terminals in the computer network described above are controlled independently. Consequently, one display terminal cannot help to alleviate the display real estate problems associated with a second terminal.
Another disadvantage with existing computer systems is that status/notification information cannot be viewed when the display monitor is off or in a screen saver mode, or when the host computer is off. A select few newer operating systems include “hibernate” or “sleep” modes where the host computer periodically wakes up and checks status, for example the computer may check whether an email has been received. Thus, the status/notification functionality is not always available to the user except in the few systems where the occurrence of an event (e.g., receipt of an email) wakes the system up to indicate the status. Typically in this instance, the system periodically provides an indication of notification/status to the user, thus not always providing the indication on the display monitor. Accordingly, there is a need to provide a system in which a user may be able to view status/notification information at all times irrespective of the power status of the main computer.